A lack of exercise may be twice as deadly as obesity, a new U.K. study suggests.

Researchers from the University of Cambridge analyzed the data of 334,000 European men and women who were participants of a European health study, which measured height, weight and waist circumference over 12 years while using self-assessment to measure physical activity.

The research showed that a brisk walk of 20 minutes per day reduced the risk of premature death by between 16% and 30%. The impact was the highest in people of normal weight, but there were benefits for those with a higher body mass index also, the study stated.

"This is a simple message: just a small amount of physical activity each day could have substantial health benefits for people who are physically inactive," said Prof. Ulf Ekelund of the Medical Research Council (MRC) Epidemiology Unit at Cambridge University. Ekelund added that 20 minutes was the minimum and people should strive for more daily exercise.

The study was published in the American Journal of Clinical Nutrition.